In recent years, with the widespread use of projectors and large-sized displays, it becomes possible to use all over the place in a space as a display unit. For example, the display screen of a terminal, such as a smartphone, a tablet terminal, or the like that is brought in by a user is displayed onto the display unit at that site, and the screen is being shared among multiple persons.
Further, a conference, a brain storming session, or the like is being conducted while an object displayed by a display device, such as a projector, or the like onto a large-sized screen is being shared among a plurality of users, and freely moved and operated. An object may be information to be displayed on a display screen and includes information, for example, text, images, icons, labels, notes, or the like and may receive operation by a user, such as movement, changes in the direction and the size, deletion, editing, or the like.
Input of such operation is carried out by using, for example, a pointing device. For example, when an infrared pen that projects infrared light is used as an pointing device, the locus of a light spot drawn by the light projected by the infrared pen may be captured by an imaging device, such as a camera that keeps the display screen within the angle of view, or the like, and may be input.
A related-art technique is disclosed in Japanese Laid-open Patent Publication No. 2016-184268.